1. Technical Field
The present invention is directed to an alkylated hydroxyaromatic compound substantially free of endocrine disruptive chemicals and a method of making the alkylated hydroxyaromatic compound.
2. Description of the Related Art
It is well known to catalyze the alkylation of aromatics with a variety of Lewis or Bronsted acid catalysts. Typical commercial catalysts include phosphoric acid/kieselguhr, aluminum halides, boron trifluoride, antimony chloride, stannic chloride, zinc chloride, onium poly(hydrogen fluoride), hydrogen fluoride, solid acid catalysts such as acidic sulfonic acid ion exchange resins, for example Amberlysts®, solid acid clays and acidic zeolitic materials. Alkylation with lower molecular weight olefins, such as propylene, can be carried out in the liquid or vapor phase. For alkylations with higher olefins, such as C16+ olefins, the alkylations are done in the liquid phase.
There is increasing evidence that certain synthetic and natural chemicals may act as agonists or antagonists to estrogens or androgens and may interfere in multiple ways with the action of thyroid hormones; such compounds can be called endocrine disruptors. For example, endocrine disruptors can mimic or block chemicals naturally found in the body, thereby altering the body's ability to produce hormones, interfering with the ways hormones travel through the body, and altering the concentration hormones reaching hormone receptors.
Endocrine disruptors and natural estrogens share a common mechanism of action. In normal cases, estrogenic activity is produced by binding natural estrogen to an estrogen receptor (ER) within the nucleus of the cell, followed by transcriptional activation of these occupied ERs. When endocrine disruptors are present, normal estrogenic activity is supplanted when endocrine disruptors bind an ER, causing transcriptional activation of the ER even though no natural estrogen is present. Similarly, antiestrogenic activity is produced by endocrine disruptors which bind to ERs but which do not subsequently activate the occupied ER as well as natural estrogen. Finally, selective estrogen receptor modulators (SERMs) bind to ERs, but subsequently activate cellular responses that differ from those activated by the natural estrogens. In general, all but a very small number of molecules that bind to ERs produce some activation of the receptors, as either estrogens or as SERMs.
Examples of suspected endocrine disruptors may include, for example, Dioxin, Polychlorinated biphenyls (PCBs), Polybromated biphenyls (PBBs), Hexachlorobenzene (HCB), Pentachlorophenol (PCP), 2,4,5-Trichlorophenoxy acetic acid (2,4,5-T), 2,4-Dichlorophenoxyacetic acid (2,4-D), alkylphenols such as Nonylphenol or Octylphenol, Bisphenol A, Di-2-ethylhexyl phthalate (DEHP), butylbenzyl phthalate (BBP), Di-n-butyl phthalate (DBP), Dicylclohexyl phthalate (DCHP), Diethyl phthalate (DEP), Benzo (a) pyrene, 2,4-Dichlorophenol (2,4-DPC), Di(2-ethylhexyl)adipate, Benzophenone, P-Nitrotoluene, 4-Nitrotoluene, Octachlorostyrene, Di-n-pentyl phthalate (DPP), Dihexyl phthalate (DHP), Dipropyl phthalate (DprP), Styrene dimers and trimers, N-Butyl benzene, Estradiol, Diethylhexyl adipate (DEHA), trans-chlorodane, cis-chlorodane, p-(1,1,3,3-Tetramethylbutyl)phenol (TMBP), and (2,4,-Dichlorophenoxy) acetic acid (2,4-PA).
Alkylphenols and products produced by them have come under increased scrutiny due to their association as potential endocrine disruptive components, which is namely due to the weak estrogenic activity of base alkylphenol as well as degradation intermediates of the alkylphenols products. Alkylphenols commercially are used in herbicides, gasoline additives, dyestuffs, polymer additives, surfactants, lubricating oil additives and antioxidants. In the recent years, alkylphenol alkoxylates, such as ethoxylated nonylphenol, have been criticized for having poor biodegradability, high aquatic toxicity of the by-products of the biodegradation of the phenol portion, and there is an increasing concern that these chemicals may act as endocrine disruptors. Some studies have shown that there are links between alkylphenols and declining sperm count in human males and there is evidence that alkylphenols may harmfully disrupt the activity of human estrogen and androgen receptors.
Concern over the environmental and health impact of alkoxylated alkylphenols has led to governmental restriction on the use of these surfactants in Europe, as well as voluntary industrial restrictions in the United States. Many industries have attempted to replace these preferred alkoxylated alkylphenol surfactants with alkoxylated linear and branched alkyl primary and secondary alcohols, but have encountered problems with odor, performance, formulating, and increased costs. The odor and some of the performance difficulties of the alkoxylated alkyl alcohols are related to the residual free alcohol, which is the portion of the reactant alcohol that does not react with alkylene oxide during the alkoxylation step.
U.S. Pat. No. 4,475,001 discloses a process for alkylating phenolic compounds to produce ortho- or para-monoalkylated phenols or 2,4- or 2,6-dialkylated phenols.
U.S. Pat. No. 4,873,025 discloses alkylxylene sulfonate composition prepared by alkylating a para-xylene reactant (or mixture of xylene isomers containing at least about 25 wt % para-xylene), sulfonating the resulting alkylate, and, optionally, converting the product alkylxylene sulfonic acid(s) into the salts. The alkylation may be carried out in a manner known for analogous compounds, e.g., by a Friedel-Crafts reactions using alkyl halide, alkanol, or alkene reactant, in the presence of a Lewis acid catalyst. Preferably the catalyst is hydrogen fluouride or an activated clay.
U.S. Pat. No. 4,912,264 disclose a process for producing hydroxyl-containing alkylated aromatic compounds by the liquid phase reaction of an aromatic compound having at least one hydroxyl group with an alkylating agent in the presence of a heteropoly acid and water.
U.S. Pat. No. 4,973,764 discloses a process for alkylating phenols wherein phenols are alkylated with the olefin component of a thermally cracked sulfur containing petroleum distillate derived from residua in the presence of an acid catalyst to provide monoalkylphenols which have an average of less than two alkyl branches in the said alkyl group.
U.S. Pat. No. 5,922,922 discloses an alkylated aromatic hydrocarbon that is produced having the following properties: (a) less than 40 wt. % of the alkylated aromatic hydrocarbon is 2-aryl; and (b) at least 20 wt. % of the alkylated aromatic hydrocarbon is a monoaklylate.
U.S. Pat. No. 6,765,106 discloses a process for preparing branched olefins comprising 0.5% or less quaternary aliphatic carbon atoms, which process comprises dehydrogenating an isoparaffinic composition over a suitable catalyst which isoparaffinic composition comprises paraffins having a carbon number in the range of from 7 to 35, of which paraffins at least a portion of the molecules is branched, the average number of branches per paraffin molecule being at least 0.7 and the branching comprising methyl and optionally ethyl branches, and which isoparaffinic composition may be obtained by hydrocracking and hydroisomerization of a paraffinic wax.
U.S. Pat. No. 7,022,763 discloses a branched olefin copolymer and a method for making said copolymer. The branched moiety is formed by radical polymerization reaction or anion polymerization reaction.
U.S. Pat. No. 7,041,864 discloses a method for producing linear and/or branched unsaturated product hydrocarbons used ring opening cross-metathesis.
U.S. Pat. No. 7,087,777 discloses a process for preparing branched olefins comprising 0.5% or less quaternary aliphatic carbon atoms, which process comprises dehydrogenating an isoparaffinic composition over a suitable catalyst which isoparaffinic composition comprises paraffins having a carbon number in the range of from 7 to 35, of which paraffins at least a portion of the molecules is branched, the average number of branches per paraffin molecule being at least 0.7 and the branching comprising methyl and optionally ethyl branches, and which isoparaffinic composition may be obtained by hydrocracking and hydroisomerization of a paraffinic wax.
U.S. Pat. No. 7,157,613 discloses a process for producing branched olefins from a mixed linear olefin/paraffin isomerisation feed comprising linear olefins.
Pac et al. Czechoslovakian Patent No. 226,912 (“Pac et al.”) disclose a process for alkylating a hydroxyaromatic compound by alkylating a phenol or substituted phenol with a propylene oligomer having a minimum content of 0.25 molar equivalents of vinylidene groups in the course of catalysis of bleaching clay or bleaching clay treated with phosphoric acid or p-toluenesulfonic acid. Pac et al. further disclose that the catalysts used in the process therein are weak alkylation catalyst.
It would be desirable to provide improved alkylated hydroxyaromatic compounds, which are substantially free of endocrine disruptive chemicals.